The present invention relates to monitoring or investigating the structural health of a structure or object, and more particularly to transducer health diagnostics for piezoelectric based structural health monitoring or management (SHM) systems.
New, lightweight composite materials, traditional metallic materials, and other materials are being used and optimized in designs more extensively in the aerospace industry for commercial aircraft and other aerospace vehicles, as well as in civil infrastructure, ground transportation, and other industries. The new materials and new designs may be subject to extreme stresses or potential damage from an impact or other cause. For example near a fuselage cargo door surround of a commercial aircraft, baggage handlers often inadvertently collide with and cause impact damage to the airplane fuselage. Any such damage needs to be quickly and efficiently identified, located, and the size and extend determined so that any needed repairs can be performed and to reduce airplane maintenance costs and eliminate airplane cancellation and delays. To implement quick non-destructive evaluations that may be performed quickly to ensure minimal maintenance times, numerous transducers or sensors are required to transmit and receive signals to detect any anomalies or damage. Transmitted and received signal quality can directly affect overall damage or anomaly detection and mapping performance. Accordingly, being able to differentiate between “good” transducers and “bad” transducers can significantly improve the fidelity and reliability of SHM systems since the transducers themselves and the bond of the transducers to the structure are also susceptible to damage.